JP2785779B2 - Stirling refrigerator and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Stirling refrigerating machine in which a compressor and an expander are connected by a connecting pipe and a method of manufacturing the same, and more particularly, to a structure of a connecting portion of the connecting pipe in the compressor and its structure. The present invention relates to a production method for obtaining

[0002]

2. Description of the Related Art Conventionally, as a kind of a small refrigerator for generating cryogenic temperature, for example, Japanese Patent Laid-Open No. 4-263 is disclosed.
No. 751 discloses a free displacer type Stirling refrigerator. This refrigerator is configured such that a compressor that compresses refrigerant gas and an expander that expands refrigerant gas discharged from the compressor are connected by a connection pipe.

In the compressor, a compression mechanism is housed in a closed cylindrical casing, and gas pressure generated in a compression chamber inside the compression mechanism is supplied to the expander through a connecting pipe.
In particular, in the case where a compression chamber is formed between a pair of pistons disposed opposite to each other as disclosed in the above-mentioned publication, a connection pipe is connected to the outer peripheral surface of the compressor casing. . A sealing structure using an O-ring or the like is adopted at a connection portion between the outer peripheral surface of the compressor casing and the connection pipe so as to prevent refrigerant leakage, and a flat surface for arranging the O-ring or the like is provided. Must be formed on the outer peripheral surface of the compressor casing.

Conventionally, as a structure for securing this flat surface, FIGS. 7 and 8 (FIG. 8 shows VI
As shown in the sectional view taken along the line II-VIII), a part of the outer peripheral surface of the casing (a) was cut off to form the connecting pipe connection surface (b) having a flat surface having a predetermined area. As a manufacturing process of the casing (a), first, the casing material is formed into a cylindrical shape by a cutting operation using a lathe, and then a part of the outer peripheral surface is cut off to form a connecting pipe connection surface (b), Thereafter, a gas discharge hole (c) is formed at the center of the connecting pipe connection surface (b). Then, the connecting pipe (d) (FIG. 8)
The connecting pipe (d) is connected to the connecting pipe connecting surface (b) such that the phantom line communicates with the gas discharge hole (c). In other words, the flange (e) of the connecting pipe (d) is overlapped with the connecting pipe connecting surface (b) via an O-ring or a metal seal (not shown), so that the sealing property of the connecting portion is ensured.
(d) was connected to the casing (a).

[0005]

In the structure described above, a part of the outer peripheral surface of the casing (a) is cut off to form the connecting pipe connecting surface (b). The thickness dimension (dimension t1 in FIG. 8) is smaller than the dimensions (t2) of the other parts. In addition, the casing (a) needs a minimum wall thickness required to maintain its strength. For this reason, the formation portion (portion of the thickness dimension t1) of the connecting pipe connection surface (b) having the smallest wall thickness dimension is set to the required minimum wall thickness dimension. The thickness dimension (t2) of the casing needs to be set large in advance in consideration of the dimension (t2-t1). That is,
Since the thickness of the connecting pipe (d) other than the connecting part must be set large, the weight of the casing (a) increases, and there is a limit to reducing the weight of the entire compressor. was there.

It is also conceivable to cut the thickness of the entire casing to the required minimum thickness after manufacturing the casing as described above, but this operation is extremely difficult, and the processing operation is complicated. It is not practical because it leads to an increase in processing cost and processing cost.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and reduces the weight of a casing by forming a flat surface for connecting a connecting pipe on the outer peripheral surface of a compressor casing by a simple processing operation. The purpose is to aim.

[0008]

In order to achieve the above-mentioned object, the present invention provides a means in which only a portion of the outer peripheral surface of a compressor casing for connecting a connecting pipe is thickened in a circumferential direction. A flat surface for connecting pipe connection was formed by cutting out a part of this thick portion.

More specifically, the present invention provides a compressor (1) having a compression mechanism in a cylindrical casing (3).
The outer peripheral surface of the compressor and the expander (2) are connected by a connecting pipe (9), and the refrigerant compressed by the compressor (1) is supplied to the expander (2) by the connecting pipe (9). )) Is based on the assumption that a Stirling refrigerator that expands the refrigerant to generate cold. Then, in the casing (3), a band-shaped portion (18) having a thick portion (18a) in which a part of the outer peripheral surface bulges to the outer peripheral side and extends in the circumferential direction is formed, and the band-shaped portion (18) is formed on the band-shaped portion (18). , Thick part (18a)
A part of the outer surface is cut off to form a flat connecting pipe connecting surface (17) for connecting the connecting pipe (9).

With this configuration, when the Stirling refrigerator is driven, the refrigerant compressed by the compressor (1) is connected to the connecting pipe.
The refrigerant is supplied to the expander (2) by (9), and the refrigerant expands in the expander (2), so that cold occurs. The connecting pipe connecting surface (17) provided on the casing (3) of the compressor (1) for connecting the connecting pipe (9) has a part of the outer peripheral surface of the casing (3) expanded to the outer peripheral side. It is formed by cutting off a part of the outer surface of the thick part (18a) that extends out and extends in the circumferential direction. For this reason, it is not necessary to form thick portions other than the band portion (18) where the thick portion (18a) is formed. In other words, the portion other than the band-shaped portion (18) can be set to the required minimum thickness, and the connecting pipe connection surface can be formed without requiring post-processing for making the entire casing (3) thin. The weight of the casing (3) can be reduced while securing (17).

According to a second aspect of the present invention, in the Stirling refrigerating machine according to the first aspect, a portion other than the band portion (18) in the casing (3) is provided with a thin portion (19) having a minimum required thickness. ), The width of the band (18),
The dimension in the axial direction of the casing (3) on the connecting pipe connection surface (17) is set so as to be at least the dimension required for connecting the connecting pipe (9). Also, the thick part (18a)
Thickness of the central part of the connecting pipe connecting surface (17) matches the thickness of the thin wall part (19), and the thickness of the connecting pipe connecting surface (17) in the transverse direction of the casing (3). The dimensions are set so as to be at least the dimensions required for connecting the connecting pipe (9).

With this configuration, the thickness of the thin portion (19) is set to the required minimum thickness, and the thickness of the thick portion (18a) is set to the minimum thickness of the connecting pipe connection surface (17). The thickness is set so that the thick portion has the minimum required thickness. In other words, both the thin portion (19) and the band-shaped portion (18) are set to the minimum required wall thickness, and the casing (3) can be made as light as possible without requiring post-processing. .

According to a third aspect of the present invention, in the Stirling refrigerator according to the first aspect, a plurality of flat surfaces (18) are cut off at a plurality of locations in the circumferential direction of the thick portion (18a). 1
7,18b, 18b, ...), and the plurality of flat surfaces (17,18b, 18) are formed.
b,...) are used as connecting pipe connection surfaces (17).

With this configuration, the volume of the thick portion (18a) can be reduced by simple post-processing, so that the weight of the casing (3) can be further reduced.

According to a fourth aspect of the present invention, in the Stirling refrigerator of the first aspect, the compressor (1) includes a cylinder member (4) disposed in a casing (3); 4) is disposed such that it can reciprocate relative to the cylinder member (4) with the tip portion inserted therein, and the compression chamber is provided between the cylinder member (4) and the compression member.
(7), a resilient means (14) for resiliently supporting the piston (6) with respect to the casing (3) and a compression chamber (4) in the cylinder member (4). 7)
A concave portion (4d) formed on the outer peripheral side of the piston, a magnet (11) disposed in the concave portion (4d), and forming a magnetic circuit using the cylinder member (4) as a yoke portion, and the piston (4). 6) a bobbin (13) having a bottom portion (21) extending from the rear end portion to the outer peripheral side, and a cylindrical portion (20) extending from the outer peripheral end of the bottom portion (21) into the concave portion (4d); A coil (12) provided on the bobbin (13) and opposed to the magnet (11) so as to be located in the magnetic field of the magnetic circuit, and supplying a current to the coil (12). Thus, the piston (6) is reciprocated relative to the cylinder member (4) to compress the refrigerant in the compression chamber (7).

With this configuration, the operation of compressing the refrigerant by the compressor (1) can be specifically obtained. That is, the coil
By supplying an electric current to the cylinder (12), the piston (6) elastically supported by the elastic means (14) reciprocates relative to the cylinder member (4), and the refrigerant flows in the compression chamber (7). The refrigerant is compressed, and the pressure of the refrigerant acts on the expander (2).

According to a fifth aspect of the present invention, an outer peripheral surface of a compressor (1) having a compression mechanism in a cylindrical casing (3) and an expander (2) are connected by a connecting pipe (9). , Compressor
The method is based on a method of manufacturing a Stirling refrigerator in which the refrigerant compressed in (1) is supplied to an expander (2) through a connecting pipe (9), and the refrigerant is expanded in the expander (2) to generate cold. Then, the casing (3) is formed by cutting the outer peripheral surface while leaving a part of the outer peripheral surface of the hollow cylindrical element tube to form a thin portion (19) having a required minimum thickness, and then forming the thinned portion (19). A band-shaped portion (18) thicker than the thin-walled portion (19) is formed on a part of the surface, and then the thick-walled portion (18a) of the band-shaped portion (18) is cut off to form a flat-surface connection pipe. Form a connecting surface (17), this connecting pipe connecting surface (17)
The connecting pipe (9) is connected to the pipe.

According to this method, similarly to the first aspect of the present invention, portions other than the band-shaped portion (18) can be set to the required minimum thickness, and the entire casing (3) can be made thinner. It is possible to reduce the weight of the casing (3) while securing the connecting pipe connection surface (17) without requiring post-processing to make the casing (3).

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) Next, a first embodiment of the present invention will be described with reference to the drawings. 1 and 2 show a compressor (1) and an expander (2) for a Stirling refrigerator according to the present embodiment, respectively. First, the compressor (1) will be described. The compressor (1) is a piston-facing linear motor compressor, has a closed cylindrical casing (3), and a cylinder member (4) is disposed inside the casing (3). ing. Further, the casing (3) includes a cylindrical body (3a) having both ends opened, and disc-shaped closing plates (3b, 3b) for closing open portions at both ends of the cylindrical body (3a). . The cylinder member (4) is made of pure iron, and is provided at an outer cylinder (4a) fixed to the inner wall of the casing (3) and at a position inside the outer cylinder (4a) at a predetermined interval. Donut-shaped connecting part with the inner cylinder (4b)
(4c), a cylindrical recess (4d) concentric with the cylinder member (4) is formed between the outer cylinder (4a) and the inner cylinder (4b). Further, the inner cylinder (4b) is a part which becomes an original cylinder, and the center thereof is formed in the piston insertion hole (5).

A piston (6, 6) is inserted into the piston insertion hole (5) of the cylinder inner cylinder (4b) from each of the left and right sides in FIG. 1, and a cylinder is inserted between the pistons (6, 6). A portion surrounded by the inner cylinder (4b) is formed in the compression chamber (7). The outer diameter of the piston (6) is
(4b) is formed to have a slightly smaller diameter than the inner diameter thereof, and a small gap of, for example, about 10 μm is formed between the two, and this small gap is sealed by a clearance seal or a fluid seal to form the compression chamber (7). ) Airtightness. Further, in the present embodiment, a sealing material (6a) is provided on the outer peripheral surface of the piston (6).

The cylinder member (4) has a gas passage (8) extending radially from the piston insertion hole (5), and the inner end of the gas passage (8) is connected to the compression chamber (7). Opening,
The gas passage (8) communicates with an internal passage (9a) of a connecting pipe (9) connected to the outer peripheral surface of the casing (3), and communicates with the compressor (1) through the connecting pipe (9). Machine (2) is connected.

The pistons (6, 6) are drivingly connected to linear motors (10, 10) for reciprocating the pistons (6, 6). That is, each linear motor (10,10)
Has a permanent magnet (11) and a coil (12).
The permanent magnet (11) is an inner cylinder (4b) of the cylinder member (4).
Is formed of a cylindrical magnet externally fitted on the outer peripheral surface. As a result, a magnetic circuit is formed by the permanent magnet (11) using the cylinder member (4) made of pure iron as a yoke portion, and a magnetic field of a predetermined strength is formed around the periphery. The pistons (6) are integrally supported by a substantially inverted cup-shaped bobbin (13). Specifically, the bobbin (13) includes a cylindrical bobbin main body (20) and a disc-shaped piston mounting portion provided on one side edge (left and right outer edges in FIG. 1) of the bobbin main body (20). (21). And the bobbin main body (20)
In a part of the outer peripheral surface of the above, at a position facing the permanent magnet (11), a coil winding part (13a) having an outer diameter smaller than that of the other part is formed. Department
A coil (12) is wound around (13a), and the coil (12) is located in the magnetic field of the magnetic circuit.

A current introduction terminal (26, 26) is provided on the closing plate (3b) of the casing (3), and one end of a lead wire for supplying current to the coil (12) is connected to the current introduction terminal. Terminal
(26,26).

Further, inside each of the pistons (6, 6),
A spring mounting member (16) having a spring mounting seat (16a) is inserted, and at the tip of the piston (6),
A through hole is formed in the axial direction of the piston (6), and a female screw is formed in the spring mounting member (16) correspondingly. A screw (N) is screwed into the piston (6) from the distal end side. The spring mounting member (16) is
(6) is integrated. Also the casing
A spring mounting seat (3d) having the same shape as above is projected from a central portion of the closing plate (3b) of the (3) facing the piston (6), and each of the spring mounting seats (16a, 3d) is protruded. A spring (14) as an elastic means for elastically supporting the piston (6) so as to reciprocate within the cylinder member (4) is provided.

The compression mechanism is constructed in this manner, and has a predetermined frequency (for example, 5) corresponding to the natural frequency determined by the mass of each piston (6, 6) and the spring constant of the spring (14).
0Hz) AC current to the coils of both linear motors (10,10)
By energizing in synchronization with (12,12), both pistons
(6, 6) is reciprocated in the opposite direction at the above-mentioned natural frequency to generate a gas pressure of a predetermined cycle in the compression chamber (7).

The feature of this embodiment is that the compressor
Casing for connecting connecting pipe (9) to (1)
(3) The configuration of the cylindrical body (3a). Hereinafter, this cylindrical body (3a)
Will be described.

3 to 5 (FIG. 4A is a plan view of a cylindrical body,
4 (b) is a front view of the cylindrical body, and FIG. 5 is a cross-sectional view taken along the line VV in FIG. 3). The cylindrical body (3a) is a substantially cylindrical member and has an outer peripheral surface. A connecting pipe connecting surface (17) formed of a flat surface for connecting the connecting pipe (9) is formed on a part of the connecting pipe. The structure of the connecting pipe connecting surface (17) and its peripheral portion will be described. Of the outer peripheral surface of the cylindrical body (3a), the cylindrical body (3
Only the substantially central portion in the axial direction of (a) is formed as a thick portion (18a) which bulges to the outer peripheral side and extends in the circumferential direction, and the thick portion (18a) forms the entire circumferential portion of the casing (3). An annular band portion (18) is formed around the circumference. In other words, the thickness of the band-shaped portion (18) is set to be slightly larger than the other portions (hereinafter, referred to as the thin portion (19)). The thickness of the thin portion (19) is set to the minimum required size in view of the strength of the compressor casing (3). Then, the thick pipe portion (18a) of a part of the surface of the strip portion (18) is cut off to form the connecting pipe connection surface (17) having a flat surface.

Hereinafter, the band-shaped portion (18) and the connecting pipe connecting surface (1)
The manufacturing process 7) will be described. First, a casing material is formed into a substantially cylindrical hollow body by a cutting operation using a lathe. At this time, the processing of the inner peripheral surface is performed so that the inner diameter dimension is uniform throughout. On the other hand, in the processing of the outer peripheral surface, cutting is performed while leaving a part of the outer peripheral surface (the central portion in the axial direction), whereby the thin portion (1
Form 9). Then, on a part of the remaining outer peripheral surface,
A band-like portion (18) thicker than the thin portion (19) is formed. Then, a part of the thick portion (18a) of the strip portion (18) is cut off to form the connecting pipe connection surface (17). At this time, the band (1
The cut size is set so that the thickness of the central portion of the connecting pipe connection surface (17) in 8) matches the thickness of the thin portion (19). Therefore, as shown in FIG.
Is formed as a flat surface extending in the tangential direction of the thin portion (19), and the thickness of the band-shaped portion (18) at the portion where the connecting pipe connection surface (17) is formed is set to be equal to or larger than the required minimum size. It will be. The width dimension (dimension A in FIG. 4 (a)) of the strip portion (18) is determined by the casing (3) on the connecting pipe connection surface (17).
Is set to be at least the dimension required for connecting the connecting pipe (9), that is, the dimension of the flange (9a) of the connecting pipe (9) described later,
8a), the thickness of the central portion of the connecting pipe connecting surface (17) matches the thickness of the thin portion (19) as described above, and the casing (3) at the connecting pipe connecting surface (17) ) In the transverse direction (dimension B in FIG. 4 (a)) is set so as to be at least the dimension required for connecting the connecting pipe (9).

After the strip 18 and the connecting pipe connecting surface 17 are formed in this way, a gas discharge hole 17a is formed at the center of the connecting pipe connecting face 17. Thus, the working of the cylindrical body (3a) of the compressor casing (3) is completed.

Next, the operation of connecting the connecting pipe (9) to the connecting pipe connecting surface (17) will be described. As shown in FIGS. 1 and 5, a flange (9b) extending outward from the distal end of the connecting pipe (9) is formed integrally with the connecting pipe (9) at a position having a predetermined dimension. 9) At the tip of
The flange (9b) is brought into contact with the connecting pipe connecting surface (17) in a state where the flange (9b) is inserted into the gas passage (8). An O-ring or metal packing (not shown) for preventing gas leakage is interposed between the flange (9b) and the connecting pipe connection surface (17). Then, connect this flange (9b) to the connecting pipe connection surface.
(17) is fastened by means of screws or the like, thereby completing the work of connecting the connecting pipe (9) to the compressor (1).

Next, the expander (2) to which the refrigerant is supplied by the connecting pipe (9) will be described. This expander (2)
As shown in FIG. 2, a cylinder (30) is provided, and a free displacer (31) is reciprocally fitted into the cylinder (30). The free displacer (31) divides the space inside the cylinder (30) into an expansion chamber (30a) and a working chamber (30b). A displacer spring (32) composed of a coil spring for elastically supporting the free displacer (31) on the cylinder (30) is provided in the working chamber (30b), and inside the free displacer (31). It is filled with metal cold storage material (31a). Also,
A first communication hole through which refrigerant gas flows between the free displacer (31) and the expansion chamber (30a) is provided at an end of the free displacer (31).
While (31b) is provided, a second communication hole (31c) through which refrigerant gas flows between the working chamber (30b) and the working chamber (30b) is provided at the end on the working chamber (30b) side. The working chamber (30b) communicates with a compression chamber (7) of the compressor (1) via a communication pipe (9).

Next, the operation of the above-structured Stirling refrigerator will be described. During this operation,
The coil (1) of both linear motors (10, 10) in the compressor (1)
An alternating current of a predetermined frequency (50 Hz) is synchronously applied to (2,12), and the coils (12,12) and (12,12) The pistons (6, 6) reciprocate in opposite directions while deforming the springs (14).
Move in synchronization with each other in the cylinder member (4), the volume of the compression chamber (7) increases or decreases, and a pressure wave of a predetermined cycle is generated in the compression chamber (7). And this compression chamber (7) is connected pipe
(9) communicates with the expander (2).
In (2), the free displacer (31) reciprocates in the same cycle as the pressure wave in the compression chamber (7), and the expansion of the gas in the expansion chamber (30a) causes chilling.
By repeating the reciprocation of (31), the cold head at the tip of the cylinder (30) is cooled to the cryogenic level.

As described above, in the present embodiment, the outer peripheral surface of the compressor casing (3) is partially bulged in the circumferential direction, and the bulged portion is cut off to form a connecting pipe connection. Since the flat surface (17) is formed, there is no need to previously set the thickness dimension of the casing to be large as in the conventional case where a part of the outer peripheral surface of the compressor casing is simply cut off. In addition, the compressor casing (3) can be used without post-processing to cut the thickness of the entire casing to the required minimum thickness.
Can be set to the required minimum thickness dimension.
Because of this, the compressor casing
The casing (3) can be reduced in weight while forming a flat surface (17) for connecting the connecting pipe on the outer peripheral surface of (3).

(Second Embodiment) Next, a second embodiment of the present invention will be described. This embodiment is a modified example of the band portion (18), and the other portions are the same as those of the first embodiment described above. Therefore, only the structure of the band portion (18) will be described here.

As shown in FIG. 6, the outer peripheral surface of the belt-shaped portion (18) formed in the same manner as in the first embodiment is cut at a plurality of positions in the circumferential direction to form a plurality of flat surfaces (18). 17,18b, 18
b, ...), and the plurality of flat surfaces (17, 18b, 18b,
...) is a connecting pipe connecting surface (17).

Each flat surface (17, 18b, 18b,...) Of the present embodiment
The connection pipe connection surface (17) of the first embodiment described above
Similarly to the above, the cutout dimension is set so that the thickness dimension of the central portion matches the thickness dimension of the thin portion (19). For this reason, the thickness dimension of the thick portion (18) at the formation portion of each of the flat surfaces (17, 18b, 18b,...) Is set to be equal to or larger than the necessary minimum dimension.

As described above, according to the configuration of the present embodiment, the flat surface (17, 18b, 18b,...) Is formed over the entire circumference of the band-shaped portion (18), so that the above-described first embodiment is realized. Thus, the volume of the band portion (18) can be reduced as compared with the case where substantially the entire band portion (18) is left in an annular shape, and the compressor casing can be formed by simple post-processing such as manual operation by an operator. (3) It is possible to further reduce the weight. Further, since the compressor casing (3) does not inadvertently roll due to the circumferential flat surface (17, 18b, 18b,...) Of the cylindrical body (3a), the work of assembling the compression mechanism and the connecting pipe ( Good workability of the connection work of 9) will be obtained.

In each of the above-described embodiments, the connecting pipe connection surface (1
Although the thickness of the central portion of (7) is set to the necessary minimum thickness similar to the thin portion (19), the present invention is not limited to this, and the thickness of the entire connecting pipe connection surface (17) is not limited to this. The dimension may be set larger than the thin portion (19).

Further, the compressor of the type in which the sealing member (6a) is interposed between the cylinder member (4) and the piston (6) has been described, but the compressor is described between the cylinder member (4) and the piston (6). The present invention may be applied to a non-contact type compressor set to have a small gap.

[0040]

As described above, according to the present invention, the following effects can be obtained. According to the first aspect of the present invention, a part of the outer peripheral surface of the compressor casing to which the connecting pipe is connected is expanded toward the outer peripheral side with respect to the Stirling refrigerator in which the compressor and the expander are connected by the connecting pipe. And a part of the outer surface is cut off to form a connecting pipe connecting surface for connecting the connecting pipe. It is not necessary to set the thickness of the casing to a large value in advance as in the case of the above, and it is not necessary to cut the thickness of the entire casing to the required minimum thickness by post-processing. Can be made thinner. For this reason, with simple processing work,
The casing can be reduced in weight while forming a flat surface for connecting the connecting pipe on the outer peripheral surface of the compressor casing, whereby the weight of the entire Stirling refrigerator can be reduced.

According to the second aspect of the present invention, the width of the band-shaped portion is set such that the dimension of the casing on the connecting pipe connection surface in the axial direction is at least equal to or more than the dimension required for connecting the connecting pipe. In addition, the thickness of the thick portion is such that the thickness of the central portion of the connecting pipe connection surface matches the thickness of the thin portion, and the dimension in the transverse direction of the casing at the connecting pipe connection surface is at least the connecting pipe. Since the thickness is set to be greater than the required size, both the thin portion and the band-shaped portion can be set to the minimum necessary thickness, and the casing is made as light as possible without requiring post-processing. Therefore, the dimensions of each part of the casing can be optimized.

According to the third aspect of the present invention, the belt-like portion has
A plurality of flat surfaces are formed by cutting the circumferential direction of the thick portion at a plurality of locations, and one of the plurality of flat surfaces is used as a connecting pipe connection surface. Since the volume can be reduced, the weight of the casing can be further reduced, and the practicality of the Stirling refrigerator can be further improved.

According to the fourth aspect of the invention, the structure of the compressor can be specifically obtained, and the practicality of the Stirling refrigerator can be improved.

According to the method of manufacturing a Stirling refrigerating machine according to the fifth aspect of the present invention, similarly to the first aspect of the present invention, portions other than the belt-shaped portion can be set to the required minimum thickness. In addition, it is possible to reduce the weight of the casing while securing the connecting pipe connection surface without requiring post-processing for making the entire casing thin.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an internal structure of a linear motor compressor.

FIG. 2 is a sectional view showing an internal structure of the expander.

FIG. 3 is a perspective view showing a cylindrical body of a compressor casing in the first embodiment.

4A is a plan view of a cylindrical body, and FIG. 4B is a front view of the cylindrical body.

FIG. 5 is a sectional view taken along line VV of FIG. 3;

FIG. 6 is a diagram corresponding to FIG. 3 in a second embodiment.

FIG. 7 is a diagram corresponding to FIG. 3 in a conventional example.

8 is a sectional view taken along the line VIII-VIII in FIG.

[Explanation of symbols]

 (1) Compressor (2) Expander (3) Casing (4) Cylinder member (4d) Recess (6) Piston (7) Compression chamber (9) Connecting pipe (11) Permanent magnet (12) Coil (13) Bobbin (14) Spring (elastic means) (17) Connecting pipe connection surface (18) Strip (18a) Thick part (18b) Flat surface (19) Thin part (20) Bobbin body (cylindrical part) (21) Piston mounting part (bottom part)

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁶ , DB name) F25B 9/14 520

Claims (5)

(57) [Claims] An outer peripheral surface of a compressor (1) having a compression mechanism in a cylindrical casing (3) and an expander (2) are connected by a connecting pipe.
The Stirling refrigerating machine connected by (9) and compressed by the compressor (1) is supplied to the expander (2) by the connecting pipe (9), and the refrigerant is expanded in the expander (2) to generate cold. In the machine, the casing (3) has a band-shaped portion (18) having a thick portion (18a) in which a part of the outer peripheral surface bulges to the outer peripheral side and extends in the circumferential direction.
A part of the outer surface of the thick portion (18a) is cut off from the strip (18) to form a flat connecting pipe connecting surface (17) for connecting the connecting pipe (9). A Stirling refrigerator comprising: 2. A portion other than the band portion (18) in the casing (3) is formed as a thin portion (19) set to a required minimum thickness, and the width of the band portion (18) is The dimension of the casing (3) in the axial direction at the connecting pipe connection surface (17) is at least
The thickness of the thick part (18a) is set to be greater than the required dimension for connecting (9), and the thickness of the central part of the connecting pipe connection surface (17) is thinner (19). Of the casing (3) at the connecting pipe connection surface (17) should be at least larger than the dimension required for connecting the connecting pipe (9). The Stirling refrigerator according to claim 1, wherein: 3. A plurality of flat surfaces (17, 18b, 18b,...) Are formed by cutting the circumferential portion of the thick portion (18a) at a plurality of locations in the strip portion (18).
Are formed, and the plurality of flat surfaces (17, 18b, 18b,...)
2. A Stirling refrigerator according to claim 1, wherein at least one of them is a connecting pipe connecting surface (17). 4. A compressor (1) comprising: a cylinder member (4) disposed in a casing (3); and a cylinder member (4) having a distal end inserted into the cylinder member (4). A piston (6) which is arranged so as to be capable of reciprocating relative to (4) and forms a compression chamber (7) with the cylinder member (4); An elastic means (14) for elastically supporting the casing (3) in a reciprocating manner with respect to the casing (3); a concave portion (4d) formed on the outer peripheral side of the compression chamber (7) in the cylinder member (4); A magnet (11) disposed in the recess (4d) and forming a magnetic circuit with the cylinder member (4) as a yoke portion, and a bottom portion (2) extending outward from the rear end of the piston (6).
1), a bobbin (13) having a cylindrical portion (20) extending from the outer peripheral end of the bottom portion (21) into the recessed portion (4d), and provided on the bobbin (13); Coil (12) placed opposite magnet (11) to be located in the magnetic field
The piston is provided by supplying an electric current to the coil (12).
2. A Stirling refrigerator according to claim 1, wherein the refrigerant is reciprocated relative to the cylinder member to compress the refrigerant in the compression chamber. 5. An outer peripheral surface of a compressor (1) having a compression mechanism in a cylindrical casing (3) and an expander (2) are connected by a connecting pipe.
The Stirling refrigerating machine connected by (9) and compressed by the compressor (1) is supplied to the expander (2) by the connecting pipe (9), and the refrigerant is expanded in the expander (2) to generate cold. The casing (3), the outer peripheral surface of the cylindrical hollow body is cut except for a part of the outer peripheral surface, and a thin-walled portion (1
After forming 9), a thin part (1
9) to form a thicker band (18), and then the band (1)
A part of the thick portion (18a) of (8) is cut off to form a flat connecting surface (17), and the connecting surface (17) is connected to the connecting surface (17).
And a method of manufacturing a Stirling refrigerator.